Passenger transportation devices, such as escalators, having a moving passenger stairway and handrail, are well known in the art. The handrail drive assemblies for such escalators usually consist of a traction roller, composed of an elastomer material such as rubber or polyurethane, as taught by Clark, in U.S. Pat. No. 3,414,109, and Taher et al, in U.S. Pat. No. 3,779,360.
The major problem associated with such driving rollers, is finding a materials composition that will provide both high strength in terms of high abrasion resistance, and a high coefficient of friction, to provide good traction through the driving wheel to move the handrail.
Fukuyama et al, in U.S. Pat. No. 3,490,119, attempted to solve these problems by providing a rubber roll, comprising a metal core, covered with a thermoset resin impregnated fiber layer, and having an outer, cast rubber layer of abrasion trimmed 20 millimeter thick polyurethane. The polyurethane consisted of the reaction product of 12 parts of methylene bis(O-chloroaniline) per 100 parts of a polyoxytetramethylene containing polyurethane prepolymer. This materials composition would provide an outer roller surface having good strength and wear resistance but only moderately good traction properties even after abrasion treatment, i.e. rolling coefficients of friction, in the probably range of about 0.50 to 0.85. What is needed is an abrasion resistant, higher traction roller, which can be used to drive escalator handrails, or any other movable plastic, rubber or metal belt.